The process of passing water through a bed of zeolite removes: MCQ with Answer and Explanation

Explanation:
Borosilicate glass (e.g., Pyrex) contains boron trioxide (B₂O₃) along with silica, giving it low coefficient of thermal expansion, thus resistant to cracking under temperature changes. Soda-lime glass is ordinary glass, used for bottles, windows. Lead crystal has high refractive index for decorative items. Quartz glass (pure SiO₂) has very high melting point but is expensive. Borosilicate is ideal for beakers, test tubes.

Explanation:
Atomic number 15 is phosphorus. Electronic configuration: 2, 8, 5. Number of shells = 3 (Period 3). Valence electrons = 5, so it is in group 15 (10+5) for p-block elements. Group 5 is for d-block. Thus Group 15, Period 3.

Explanation:
A negative catalyst (inhibitor) slows down a reaction. Phosphoric acid (or acetamide) retards the decomposition of H₂O₂ by stabilizing it. MnO₂ is a positive catalyst for H₂O₂ decomposition, speeding it up. Platinum catalyzes SO₂ oxidation in contact process. Iron (Fe) catalyzes ammonia synthesis in Haber process. Negative catalysts are often used to prevent undesirable reactions, e.g., antioxidants in food preservation.